GB741040A - A process and apparatus for the manufacture of cup-, box- or dish-like hollow bodies from thermoplastic foil - Google Patents

Abstract

741,040. Blow-moulding hollow articles from thermoplastic foil. KUNST IM DRUCK OBPACHER AKT.-GES. Dec. 30, 1953 [Jan. 22, 1953], No. 36114/53. Class 87 (2). [Also in Group XVII] Polyvinyl chloride foil 35, Fig. 1, is led from a spool 10 to the space between a lower stationary platen 4 and an upper vertically-reciprocating platen 8, where it overlies a mould 32, Fig. 4. Compressed air from pipe 26 then passes through holes 36 in the mould base and forces the foil upwardly against the underside of the platen' 8, which is heated, Fig. 5. Then, Fig. 6, the' air supply from pipe 26 is cut off and compressed air from pipe 27 forces the heated foil down into the recesses in the (cold) mould 32 where it becomes rigid. The moulded article is then removed from the mould and cut from the end of the foil and another moulding operation is performed on the foil. The mould may be supported directly on the platen 4, but as shown it is supported bya carriage 5 that runs or slides on rails 13 between the platens and a cutting device 14. When moulding has been effected the carriage moves to the right, Fig. 12, the moulded article 40 is lifted out of the mould and moved further to the right, the cutter severs the article, the article drops on to a plate 16 or a conveyer and the foil length 35<11> that is to be moulded next is moved back leftward to the space between the platens, the third length 35<111> hanging in a bight as shown in Fig. 15. The pipes 26, 27 are supplied with compressed air from a motor-driven compressor 19 via pipes 21, 22 and valves 24, 25. When the air is cut off from the mould it passes to atmosphere via pipes 28, 29, silencer 30 and pipe 31. The air-holes 36 in the mould may be present in larger numbers at acute bends than at flat or slightly curved surfaces. The article '40 consists of a number of dish-shaped objects, which may be cut from each other, enclosed in pairs around material to be packed and highfrequency-welded together at their edges.